Method and apparatus for thermochemical metal scarfing



une 10, '1958 w'. ALLMANG E'r-AL METHOD AND APPARATUS FORTHERMocx-IEMICAL MEM. SCARFING Filed May 2e. 195s 5 Sheets-Sheet 1 June10,1958 w. ALLMNG ETAL 2,833,431

I METHOD AND APPARATUS FOR THERMOCHEMICAL METAL SCARFING Filed May26,'1955 s sheets-Sheena INVENTORS v WILLIAM ALLMANG 34x, 5 CARLE.HARTMANN 9i lvAN P.THoMPsoN ATTORN EY June 10, 1958 w. ALLMANG ETAL2,838,431

vMETHOD AND APPARATUS FOR THERMocx-IEMICAL METAL scARFING 5 Sheets-Sheet3 Filed May 26. 1953 N AAO S MS RM Y LTD.. ME m Ln.M N E Hm J@ WML T IAP A UL LMM vWCW l B United METHOD AND APPARATUS FOR THERM- CMMICAL METALSCARFING Application May 26, 1953, Serial No. 357,496

11 Claims. (Cl. 14S- 9.5)

This invention relates to therrnochemical metal scarfing, moreparticularly to method and apparatus for post-mixed preheat continuouswide oxygen stream desurfacing.

ln such desurfacing, it has been necessary to provide three systems ofgas supply. In addition to the main stream of oxidizing gas, the preheatflames to start and stabilize the reaction have required a large numberof fuel gas jets, and a supply of preheat oxidizing gas to supportcombustion thereof. The development of postmixed preheat flames toeliminate flashbacks vhas required a corresponding number of individualoxidizing gas streams, a separate stream for each fuel gas jet tosupport combustion thereof. The supply and distribution of these preheatoxidizing gas streams has been expensive as to first cost andmaintenance.

It is therefore the main object of the present invention to eliminatethe separate supply of preheat oxidizing gas. This We accomplish byutilizing the main stream of oxidizing gas as a source of supply ofpreheat oxygen for the fuel gas preheat flames. I

It has also been desirable to bring the cutting stream of oxidizing gasand the upper preheat flames close to the zone of reaction, but priorexpedients have resulted in damage to the orifices by scabs and sliversprojecting from the work.. It is therefore another object -to space theorifices above the worlt to clear such scabs and slivers, whileconfining the stream of oxidizing gas and directing the preheat flamesclose to thezone of reaction. This we accomplish by increasing the angleof impingement to about 30 and extending the upper surface of theoxidizing gas slot beyond the lower surface thereof to bring the uppersurface closer to the work than the lower surface thereof.

Heretofore the nozzle siotfor the cutting stream of oxidizing gas hasbeen manufactured as an insert, which was difficult and expensive tomanufacture and replace. It is therefore another object to facilitateand economize the manufacture of this slot. This we accomplish by abuilt-in construction. Y

Another object is to provide a ywide slot nozzle unit adapted to producea flared strearmwhereby a plurality of such units placed side by sidefor scarng slabs, will have their flared streams merge to prevent aridge therebetween,

Other objects and features of novelty will be apparent from thefollowing description and the accompanying drawings, in which:

Fig. l is a vertical section through a desurfacing head according to,and for carrying out the method of, the present invention;

Fig. 2 is an exploded view of parts lshown in Fig. 1;

Fig. 3 is a perspective View of the front and bottom of the nozzleblocks;

Fig. 4 is similar view of the rear of the nozzle blocks;

Fig. 5 is a section taken along the line5-5 of Fig. l;

Fig. 6 is a section taken along the line 6-6 of Fig. l;

Fig. 7 is a section taken along the line 7-7 of Fig. l;

rates Fatem O Patented June 10, 1958.

Fig. 8 is a section through the preheat fuel gas ports; and

Fig. 9 is a plan of the water cooled skid plate.

Referring more particularly to the drawings, the desurfacing headcomprises a nozzle base block 10, a skid block 12, an upper lip plate 14and a lower lip plate 15. The nozzle base block 10 is bolted andgasketed to a manifold block 16, which comprises a selector valveassembly as disclosed in the Miller andKolody Patent No. 2,524,920,issued October 10, 1950. The skid block 12 is bolted to the bottom ofthe base block 10. The lip plates 14 and 15 are bolted to the front faceof the base block' 10. This face is about 60 to the horizontal, so thatthe lip plates are at about 30.

The lip plates 14 and 15 are spaced apart by end walls 18 to form thecutting slot 20 for the oxidizing gas. The upper lip plate 14 extendsforwardly as at 21 about a third of its length beyond the lower lipplate 15, to confine the stream of oxidizing gas close to the reactionzone. The end walls 18 are tapered outwardly at the forward portions oftheir inner sides as at 19, to cause the oxidizing `gas stream vtoexpand laterally and thereby provide good coverage when scarng the foursides of a bloom or billet, or to prevent ridges between adjacent unitswhen placedside by side in a slab scarfing machine.

The opposed surfaces of the lip plates 14 and 15 are provided withuniformly laterally spaced corresponding grooves 22 extending from Ytherear forward for about two-thirds of the common extent of the lipplates. These grooves 22 receive partitions 23, dividing the slot 20into parallel oxidizing gas ways 2.4. v

The oxidizing gas ways 24 register with the outlet ends of correspondinggroups of bores 26 yin the base block 10 and aligned with the centralplane of the oxidizing gas slot 20. These bores are supplied by atransverse bore 28, which, as shownin Fig. 5, receives a dividercomprising a stem 31 Vprovided with end wallsv32 and discs 33 spacedcorresponding to the slot partitions 23 and dividing the bore 28 intoequal oxidizing gas chambers 35. Each chamber 35 is 4supplied by a bore36 leading to corresponding passages 38 in the manifold block 16, andreceiving oxidizing gas therefrom in the customary manner.

The upper lip plate 14 is provided with a row of closely.

spaced bores 40 for projecting jets `of fuel gas down toward thereaction zone. These bores are supplied by a transverse bore 41 as bestshown in Figs. 7 and 8. This bore 41 receives a dividercomprising a stem.42 provided with end walls 43 and discs 4.4 spaced corresponding to theoxidizing gas partitions Ziwuand dividing the bore 41 into separate fuelgas .chambers 45. The chambersv 45 are each supplied by separate fuelgas bores 46 Aregistering ywith corresponding bores 47 in the base block1),

which in turn receive fuel` gas'from bores 48 registering with fuel gassupply bores49 inthe vmanifold Vblock 16.

For cooling the` upper lip plate 14, atransverse bore 52 isprovided,'which receives cooling lluidfrom a longitudinal bore54'show-n'in Fig. invturn receiving from passages 56 registering-withholes 58 inthe slot end wall 18. From the bore 52 the coolingfluid-passes through longitudinai bore 59 and registeringv boret) in thebase block 1t) which has a eommunicatingbore 61`leading to the Y inFigures 7l andv 8 for the lower block. The-chambers'I formed thereby arefed'by longitudinal bores-67vregister-` ing with bores 68 in the baseblock 10 communicating with the supply bores 48 from the manifoldpassage 49.

For'cooling the lower lip block 15, a transverse bore 72 is provided,which receives cooling uid from a longitudinal bore 73 supplied by avertical bore 74. From the transverse bore 72, the cooling fluid passesout through longitudinal bore 75 and passages 76 to the holes 58 in theend wall 18.

The skid block 12 contains a cooling jacket 80 which receives coolinguid from the supply passage 81 in the manifold block 16, and registeringvertical passage 82 in the base block 10, joining a transverse passage83 leading to a vertical passage 84, which registers with the skid blockentrance passage 85. The cooling jacket 80 by means of a passage 87 isin parallel relation to a bore 86 in the front of the skid block andhaving out passage 88. Furthermore, the cooling fiuid passes to outlet89 which is in register with the lower lip plate inlet 74.

We claim:

l. In a process for thermochemically scarfing metal bodies, discharginga sheet-like stream of oxidizing gas onto a reaction zone extendingacross the entire transverse extent of the surface of a metal body andat an acute angle of impingement to the work surface of said metal body,confining said sheet-like stream of oxidizing gas between upper andlower spaced apart surfaces laterally continuous for the entiretransverse extent of the surface of said body, discharging a row of jetsof preheat fuel gas at an acute angle to said oxidizing gas stream ontosaid reaction zone from a row of orifices ahead of at least one of saidsurfaces, and supplying preheat oxidizing gas from said sheet-likestream of oxidizing gas to support combustion of said jets of fuel gasand produce post-mixed preheat ames therefrom.

2. In a process for thermochemically scarfing metal bodies, discharginga sheet-like stream of oxidizing gas onto a reaction zone extendingacross the entire width of a metal body and at an acute dihedral angleof impingement to the work surface of said metal body, confining saidsheet-like stream of oxidizing gas between upper and lower spaced apartsurfaces laterally continuous for the entire width of said body,discharging a row of jets of preheat fuel gas at an acute angle to saidoxidizing gas stream onto said reaction zone from a row of orificesbelow said lower surface, and supplying preheat oxidizing gas from saidsheet-like stream of oxidizing gas to support combustion of said jets offuel gas and produce postt mixed preheat ames therefrom.

3. In a process for thermochemically scarfing metal bodies, discharginga sheet-like stream of oxidizing gas onto a reaction zone extendingacross the entire width of a metal body and at an acute dihedral angleof impingement to the work surface of said metal body, confining saidsheet-like stream of oxidizing gas between upper and lower uniformlyspaced apart surfaces laterally continnous for the entire width of saidbody, discharging a row of jets of preheat fuel gas at an acute angle tosaid oxidizing gas stream onto said reaction zone from a row of orificesabove said upper surface and impinging said stream of oxidizing gas asubstantial distance ahead of the said lower surface and supplyingpreheat oxidizing gas from said sheet-like stream of oxidizing gas tosupport combustion of said jets of fuel gas and produce postmixedpreheat ames therefrom.

4. In a process for thermochemically scarng metal bodies, discharging asheet-like stream of oxidizing gas onto a reaction zone extending acrossthe entire width of a metal body and at an acute dihedral angle ofirnpingement to the work surface of said metal body, confining saidsheet-like stream of oxidizing gas between upper and lower uniformlyspaced-apart surfaces laterally continuous for the entire width of saidbody, said Y upper surface extending smoothly and continuously forwardlybeyond said lower surface along said inclined ox- 76 idizing gasstreamin overhanging relation to said lower surface for a lengthmeasured along said stream greater than the spacing of said surfacestoward the reaction zone to terminate the confinement of the top of saidoxidizing gas stream closer to the reaction zone than the termination ofconfinement of the bottom thereof, and thereby discharge the stream ofoxidizing gas directly onto the reaction zone of the work surface,discharging a transversely distributed flow of preheat fuel gas at anacute dihedral angle to said oxidizing gas stream from transverselyarranged orifice means ahead of the termination of confinement of atleast one of said oxidizing gas stream confining surfaces, and supplyingpreheat oxidizing gas from said sheet-like stream of oxidizing gas tosupport combustion of said fuel gas to produce a transverselydistributed post-mixed preheat fiame.

5. ln apparatus for thermochemically scarng metal bodies, a desurfacinghead comprising a nozzle block, a skid plate secured to said nozzleblock and having a work engaging surface, said nozzle block having afront seating surface at an angle of about 60 to said work cngagingsurface, upper and lower lip plates having their rear ends abutting andsecured to said seating surface of said nozzle block in spaced apartrelation, side walls closing the space between said lip plates andforming a cutting oxygen slot, transversely arranged preheat fuel gasorifice means in the front face of at least one of said lip plates, saidone of said lip plates being free of any internal oxygen passages, thepreheat oxygen for said fuel gas orifice means being supplied by saidcutting oxygen slot to form transversely distributed post-mixed preheatame.

6. In apparatus for thermochemically scarfing metal bodies, adesurfacing head comprising a nozzle block, a skid plate secured to saidnozzle block and having a work engaging surface, said nozzle blockhaving a front seating surface at an angle of about 60 to said work en'gaging surface, upper and lower lip plates having their rear endsabutting and secured to said seating surface of said nozzle block inspaced apart relation, said upper lip plate extending integrallyforwardly about a third of its length beyond said lower lip plate tobring the front bottom edge of said upper lip plate below the front topedge of said lower lip plate, side walls closing the space between saidlip plates and forming a cutting oxygen slot, and means in said nozzleblock including orifice means in said front seating surface forsupplying cutting oxygen to said slot.

7. In apparatus for thermochemically scarfing metal bodies, adesurfacing head comprising a nozzle block, a skid plate secured to saidnozzle block and having .a work engaging surface, said nozzle blockhaving a plane front surface at an angle of about 60 to said workengaging surface, upper and lower lip plates having their rear endsabutting and secured to said plane front surface of said nozzle block inspaced apart relation, said upper lip plate extending integrallyforwardly about a third of its length beyond said lower lip plate tobring the front bottom edge of said upper lip plate below the front topedge of said lower lip plate, side walls closing the space between saidlip plates and forming a cutting oxygen slot, means in said nozzle blockfor supplying cutting oxygen to said slot, transversely arranged preheatfuel gas orifice means in the front face of at least one of said lipplates, fuel gas passage means in said one of said lip plates leading tosaid orifice means and corresponding fuel gas passage means in saidnozzle block leading to registering aperture means in the abuttingsurface thereof for supplying fuel gas to said orifice means.

8. In apparatus for thermochemically scarfng metal bodies, a desurfacinghead comprising a nozzle block,

`a skid plate secured to said nozzle block having a work engagingsurface, said nozzle block having a front seating surface at an angle ofabout 60 to said work engaging surface, upper and lower lipy plateshaving their rear ends abutting and secured to said seating surface ofsaid nozzle block in spaced apart relation, side walls closing the spacebetween said lip plates and forming a cutting oxygen slot, the innersurfaces of said lip plates having longitudinal grooves, verticalpartitions fitted into said grooves and dividing said slot into cuttingoxygen ways, said nozzle block having passage therein for supplyingcutting oxygen to said Ways.

9. In apparatus for thermochemically scariing metal bodies, adesurfacing head comprising a nozzle block, upper and lower lip platessecured in the front of said nozzle block in spaced apart relation, bothof said lip plates extending forward from said nozzle block for a lengthmany times the distance therebetween, and the front edge of said upperlip. plate overhanging that of said lower lip plate for a length greaterthan the distance therebetween, side walls closing the space betweensaid lip plates and forming a cutting oxygen slot, means in said nozzleblock for supplying oxidizing gas to said slot, a row of preheatoritices in the front of at least one of said lip plates, fuel gaspassages in said lip plate leading to said row of preheat orifices,corresponding fuel gas passages in said nozzle block leading toregistering apertures of said lip plate to form continuous conduits forsupplying fuel gas to said row of preheat orifices, said lip platehaving a transverse bore nearits front end, said roW of preheat orificescommunicating with said bore, and a distributor inserted in said boreand having uniformly spaced annular seals dividing said ports into equalgroups.

10. In a desurfacing head for thermochernical metal removal, a nozzleblock, upper and lower lip plates secured to said nozzle block in spacedapart relation, both of said lip lplates extending forward from saidnozzle block for a length many times the distance therebetween, and thefront edge of said upper lip plate overhanging that of said lower lipplate for a length greater than the distance therebetween, side wallsclosing the space between said lip plates and forming with the innersurface of said lip plates having longitudinal grooves, verticalpartitions fitted into said grooves and dividing said slot into cuttingoxygen ways, said nozzle block having passages therein for supplyingcutting oxygen to said ways, at least one of said lip plates having atransverse bore near its front end, a row of preheat ports in the frontof said plate communicating with said bore, and a distributor insertedin said bore and having uniformly spaced annular seals dividing saidports into equal groups.

1l. in a desurfacing head for thermochemical metal removal, a nozzleblock, upper and lower lip plates secured to the front of said nozzleblock in spaced-apart relation, both of said lip plates extending'forward from said nozzleblock for a length many times the distancetherebetween, and the front edge of said upper lip plate overhangingthat of said lower lip plate for a length greater than the distancetherebetween, side wallsv closing the space between said lip plates andforminga cutting oxygen slot, said nozzle block having a transverse borereceiving a supply of cutting oxygen, a distributor in said bore havingannular seals dividing said bore into cham-v bers, and longitudinalbores in said nozzle block communicating with said chambers and openinginto the front face of said nozzle block between said lip plates, forsupplying cutting oxygen to said slot.

References Cited in the iile of this patent UNITED STATES PATENTS1,709,886 Smith et al Apr. 23, 1929 2,266,834 Walker et al. Dec. 23,1941 2,347,758 Walker' et al. May 2, 1944 2,425,710 Buchnam et al. Aug.19, 1947 2,483,479 Smith et al Oct. 4, 1949 2,532,103 Kiernan Nov. 28,1950 2,536,609 Kemp Ian. 2, 1951 2,680,608 Buchnam et al. June 8, 19542,745,475 Thompson et al May 15, 1956

1. IN A PROCESS FOR THERMOCHEMICALLY SCARFING METAL BODIES, DISCHARGINGA SHEET-LIKE STREAM OF OXIDIZING GAS ONTO A REACTION ZONE EXTENDINGACROSS THE ENTIRE TRANSVERSE EXTENT OF THE SURFACE OF A METAL BODY ANDAT AN ACUTE ANGLE OF INPINGEMENT TO THE WORK SURFACE OF SAID METAL BODY,CONFINNG AND SHEET-LIKE STREAM OF OXIDIZING GAS BETWEEN UPPER AND LOWERSPACED APART SURFACES LATERALLY CONTINUOUS FOR THE ENTIRE TRANSVERSEEXTENT OF THE SURFACE OF SAID BODY, DISCHARGING A ROW OF JETS OF PREHEATFUEL GAS AT AN ACUTE ANGLE TO SAID OXIDIZING GAS STREAM ONTO SAIDREACTION ZONE FROM A ROW OF ORIFICES AHEAD OF AT LEAST ONE OF SAIDSURFACES, AND SUPPLYING PREHEAT OXIDIZING GAS FROM SAID SHEET-LIKESTREAM OF OXIDIZING GAS TO SUPPORT COMBUSTION OF SAID JETS OF FUEL GASAND PRODUCE POST-MIXED PREHEAT FLAMES THEREFROM.